Home Denial Codes CO-186
Denial Code CO-186

Payment denied due to eligibility (Updated for 2026)

Payment denied due to eligibility

Quick Explanation

Denial code CO-186 indicates that the claim was denied because the patient was not eligible for insurance benefits on the specified date of service. This typically occurs when a patient's policy has been terminated, has not yet become active, or does not cover the rendered services under their current plan.

Common Causes for CO-186

Denials with code CO-186 typically happen for the following specific reasons:

How to Prevent CO-186 Denials

To avoid receiving this denial in the future, implement these specific checks:

Appeal Letter Template for CO-186

If you believe this claim was denied incorrectly, you can use the following template to submit an appeal.

[Your Practice Header]
[Date]

[Payer Name]
[Appeals Department Address]

RE: Appeal for Claim [Claim Number]
Patient: [Patient Name]
ID: [Patient ID]
Date of Service: [Date]
Denial Code: CO-186 - Payment denied due to eligibility

Dear Appeals Department,

I am writing to appeal the denial of the above-referenced claim, which was denied with code CO-186: "Payment denied due to eligibility".

We are writing to appeal the denial of this claim under code CO-186 (Payment denied due to eligibility) for the service rendered on [Date of Service]. Our records and attached documentation indicate that the patient's eligibility was verified and confirmed active under policy [Policy Number] at the time of service, aligned with CMS guidelines regarding administrative reliance on payer verification systems. We have attached the clearinghouse eligibility response screen containing the active confirmation transaction number and timestamp. We request that this claim be reprocessed and reimbursement be issued as verified.

Attached please find:
1. A copy of the original claim.
2. The relevant medical records supporting the service.
3. [Any other supporting documents].

We respectfully request that you reprocess this claim for payment.

Sincerely,

[Your Name]
[Title]
[Practice Name]
            

Stop Writing Appeals Manually

Clausea can read your medical records and generate custom, evidence-based appeals for denial code CO-186 in seconds.

Generate Appeal for CO-186 Now